Systems and methods for self-aligning cutting hub assembly

ABSTRACT

A system that enables a cutter head to pivot for improved alignment with a cutting face or die is disclosed. The system includes a cutter hub and a driveshaft hub mated with a plurality of round, spherical, or ovoid surfaces to enable the cutter hub to pivot with respect to the driveshaft hub. The system can include a plurality of alignment pins with spherical surfaces to transfer torque from the driveshaft hub to the cutter hub. The system can also include a cutter head, which can include a plurality of cutting blades. The system can be used in cutting machinery, such as a pelletizer, where alignment of the cutting head and the cutting die (or other cutting surface) is desirable.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119(e) to U.S.Provisional Patent Application Ser. No. 61/867,901, filed 20 Aug. 2013,and entitled Device for Self-Aligning of Cutting Hub Assembly, theentire contents and substance of which is hereby incorporated byreference as if fully set forth below.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the present invention relate to a self-aligning cutterhub, and specifically to a self-aligning cutter hub assembly for use ina pelletizer such that the blades thereon are in proper alignment withthe die face of the extrusion die plate of the pelletizer.

2. Description of the Prior Art

Underwater pelletizers for forming pellets typically use an extrusiondie with orifices through which molten polymer is extruded.Specifically, the molten polymer is extruded out from a die face,wherein cutter blades mounted on a rotatable cutter hub cut the plastic“ribbons” into pellets. The cutter hub is generally driven by a driveshaft. The cutter blades (and thus the hub) are preferably aligned suchthat the blades themselves are substantially parallel to the die face.In this manner, the pellets are substantially uniform in shape, i.e.,the pellets from a first side of the die face are not larger thanpellets from a second side of the die face due to a misalignment.

As a result, it is desirable to maintain the cutter blades and die facein properly aligned relation so that the cutting edge of the blades onthe rotating cutter hub move in very close parallel relation to the dieface. This close parallel relationship enables the blades to efficientlycut the extruded plastic into pellets as the plastic strands aredischarged from the orifices in the extrusion die plate. As mentionedabove, parallel alignment also enables the production of substantiallyuniform pellets. Additionally, proper alignment prevents unnecessarywear of the cutter blade and/or die plate face due to interferencebetween the two and unnecessary side loading on bearings and shafts.

It is also desirable to be able to separate the cutter head from the dieplate to enable, for example and not limitation, cleaning andmaintenance, blade replacement, and inspection. Upon reassembly,however, the cutter head must be realigned with the die face.Conventional configurations have often relied on manual alignment of thecutter with the die face. Unfortunately, manually realigning the cutterhead every time the machine is serviced requires a skilled worker, asubstantial amount of time, and requires expensive and complicatedadjustment means.

What is needed, therefore, is a system and method that provides accuratealignment of the cutter head and die plate that is simple and robust.The system should provide good serviceability and performance withrelatively low equipment and maintenance costs. It is to such a systemthat embodiments of the present invention are primarily directed.

BRIEF SUMMARY OF THE INVENTION

Embodiments of the present invention can comprise a cutter hub assemblyfor a pelletizer, or other industrial machinery. The system can provide,accurately and simply, alignment of a cutter hub and die plate. Thesystem can be used on, for example and not limitation, underwater, waterring, and dry face type pelletizers. The cutter hub assembly can have aself-aligning driving connection between the cutter hub and drive shaftfor the hub in which the cutter hub is capable of universal pivotalmovement as well as a driving connection between the drive shaft andcutter hub.

The self-aligning hub assembly can comprise a shaft adapter mounted onthe end of a drive shaft, with a concave spherical surface. Theself-aligning hub assembly can also comprise a plurality of pins thathave an elongated spheroid, or rounded, surface for transmitting torque.The system can also comprise a cutting hub adaptor having a convex,spherical surface configured to mate with the concave spherical surfaceof the shaft adaptor, and recesses for the elongated spheroid shapedpins to transmit the torque for rotation of the hub. The cutting hubadaptor can further include a concave spherical surface on the oppositeside of the shaft adapter for slideable engagement with a sphericalretaining plug. The convex spherical surface of the spherical retainingplug can be sized and shaped to slideably engage with the concavespherical surface of the cutting hub adaptor. The spherical retainingplug can be held into the assembly by a fastener such as a socket headcap screw or integrated machined treads.

Embodiments of the present invention can comprise a system comprising adriveshaft adapter with a first side and a second side. The driveshaftadapter can comprise a first plurality of alignment holes disposed onthe first side and a concave surface disposed on the first side. Thedriveshaft adapter can further comprise a cutter adapter with a firstside and a second side and can comprise a second plurality of alignmentholes disposed on the second side and a convex surface disposed on thesecond side. In some embodiments, the present invention can furthercomprise a plurality of alignment pins, each with a first end and asecond end, and each of the first ends comprising a rounded surfacesized and shaped to be in slideable engagement with one or more of thefirst and second plurality of alignment holes. In some embodiments, thecutter adapter can pivot on the convex surface, concave surface, and therounded surfaces on the plurality of alignment pins to align the cutteradapter with a die face.

In some embodiments, a concave surface can be disposed on the first sideof the cutter adapter. In some embodiments, a plug adapter comprising aconvex surface sized and shaped to be in slideable engagement with theconcave surface on the first side of the cutter adapter can beconfigured to be in engagement with the driveshaft adapter.

In some embodiments, one or more of the concave surface of thedriveshaft adapter, the convex surface of the cutter adapter, theconcave surface of the cutter adapter, and the convex surface of theplug adapter can be surface treated by one or more of polishing,electro-less plating, electroplating, plasma coating, PTFE coating,composite diamond coating, or PVD coating. In some embodiments, the plugadapter can further comprise a first seal groove disposed on the convexsurface and an adapter seal sealing the convex surface of the plugadapter and the concave surface on the first side of the cutter adapter.In some embodiments, the adapter seal can be an o-ring.

In some embodiments, the cutter adapter can further comprise a firstthreaded surface disposed on an external perimeter of the cutteradapter, and there can be a toroidal cutter head comprising a pluralityof cutting blades disposed on an external perimeter surface and a secondthreaded surface disposed on an internal perimeter surface that can bethreadably engageable with the first threaded surface disposed on theexternal perimeter of the cutter adapter. In some embodiments, each ofthe plurality of cutting blades can further comprise one or moremounting fasteners detachably coupling the plurality of cutting bladesto the toroidal cutter head.

In some embodiments, the present invention can further comprise a firstgroove disposed on the first side of the driveshaft adapter, a secondgroove disposed on the second side of the cutter adapter, and a firstseal for sealing the first surface of the driveshaft adapter to thesecond surface of the cutter adapter. In some embodiments, the secondend of each of the plurality of alignment pins comprises threads forthreadable engagement with one of the driveshaft adapter and the cutteradapter.

In some embodiments, a cutter head can be attached to the cutter adapterand a force applied to the cutter head can cause the cutter adapter topivot. In some embodiments, the rounded surface on the plurality ofalignment pins comprises one or more of a surface hardness treatment anda surface lubricity treatment.

Embodiments of the present invention can further comprise a systemcomprising a power source, a driveshaft with a first end and a secondend, the first end detachably coupled to the power source, and adriveshaft adapter with a first side and a second side, the first sidedetachably coupled to the second end of the driveshaft. In someembodiments, the driveshaft adapter can comprise a first plurality ofalignment holes disposed on the second side and a concave surfacedisposed on the second side. In some embodiments, the invention canfurther comprise a cutter adapter with a first side and a second side.The cutter adapter can comprise a second plurality of alignment holesdisposed on the first side and a convex surface disposed on the firstside. In some embodiments the invention can further comprise a pluralityof alignment pins, each with a first end and a second end, each of thefirst ends comprising a rounded surface in slideable engagement with oneor more of the first and second plurality of alignment holes. In someembodiments, the cutter adapter can pivot on the convex surface, concavesurface, and rounded surfaces on the plurality of alignment pins.

In some embodiments, the invention can further comprise a die facecomprising a plurality of extrusion holes, a cutter head attached to thecutter adapter and comprising cutting blades, and the cutter adapter canpivot to align the cutting blades with the die face in parallelarrangement. In some embodiments, the cutting blades can contact the dieface and the resulting force can cause the cutter adapter to pivot.

In some embodiments, the cutter adapter can further comprise a firstthreaded surface disposed on an external perimeter of the cutteradapter, a toroidal cutter head comprising a plurality of cutting bladesdisposed on an external perimeter surface and a second threaded surfacedisposed on an internal perimeter surface and threadably engageable withthe first threaded surface disposed on the external perimeter of thecutter adapter, and the cutter adapter can pivot to align the pluralityof cutting blades with the die face in parallel arrangement.

In some embodiments, the driveshaft adapter and the plurality ofalignment pins are integrally manufactured. In some embodiments, therounded surface on the plurality of alignment pins comprises a surfacehardness treatment. In some embodiments, the rounded surface on theplurality of alignment pins comprises a surface lubricity treatment. Insome embodiments, one or more of the concave surface of the driveshaftadapter and the convex surface of the cutter adapter are surface treatedby one or more of polishing, electro-less plating, electroplating,plasma coating, PTFE (polytetrafluoroethylene) coating, compositediamond coating, or PVD (physical vapor deposition) coating.

Embodiments of the present invention can further comprise a system foraligning cutting blades with a die surface. The system can comprise adriveshaft adapter connected to a driveshaft and having a concavesurface disposed on a first side, a cutter adapter, a plug adapter witha convex surface disposed on a first side, and a cutter head attached tothe cutter adapter and comprising cutting blades. In some embodiments,the cutter adapter can pivot between the concave surface of thedriveshaft adapter and the convex surface of the plug adapter inresponse to a force applied to the cutting blades.

In some embodiments, the cutter adapter can comprise a convex surface inslideable engagement with the concave surface of the driveshaft adapterand a concave surface in slideable engagement with the convex surface ofthe plug adapter. In some embodiments, the invention can furthercomprise a plurality of alignment pins to transfer torque from thedriveshaft adapter to the cutter adapter, and the alignment pins do notprevent the cutter adapter from pivoting. In some embodiments, thealignment pins can comprise a rounded surface with one or more of asurface hardness treatment and a surface lubricity treatment.

In some embodiments, one or more of the concave surface of thedriveshaft adapter and the convex surface of the plug adapter can besurface treated by one or more of polishing, electro-less plating,electroplating, plasma coating, PTFE coating, composite diamond coating,or PVD coating.

These and other objects, features and advantages of the presentinvention will become more apparent upon reading the followingspecification in conjunction with the accompanying drawing figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 a and 1 b illustrate an isometric view of the front and rearside, respectively, of a driveshaft adapter, in accordance with someembodiments of the present invention.

FIGS. 2 a and 2 b illustrate an isometric view of the front and rearside, respectively, of a cutter adapter, in accordance with someembodiments of the present invention.

FIGS. 3 a and 3 b illustrate a schematic view and an isometric view,respectively, of an alignment pin, in accordance with some embodimentsof the present invention.

FIGS. 4 a-4 c illustrate a schematic view, a top view, and an isometricview, respectively, of a hemispherical retainer plug, in accordance withsome embodiments of the present invention.

FIG. 5 a depicts an isometric exploded view of the self-aligning cutterhub system, in accordance with some embodiments of the presentinvention.

FIG. 5 b depicts an isometric exploded view of a cutter head and acutter hub with bolting flanges, in accordance with some embodiments ofthe present invention.

FIG. 6 depicts the system installed in a pelletizer, in accordance withsome embodiments of the present invention.

FIG. 7 a illustrates a cross-sectional view of a cutter hub assembly ina parallel position, in accordance with some embodiments of the presentinvention.

FIG. 7 b illustrates a cross-sectional view of a cutter hub assembly ina position in which the system is correcting a 1° misalignment, inaccordance with some embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention relate to a system for mounting acutter head in proper alignment with a die face. The system can utilizea series of complementary spherical surfaces to provide improvedalignment of the cutting hub with the die face. In some embodiments, thesystem can also use a plurality of fasteners with spheroidal orelliptical mating surfaces to provide additional alignment.

To facilitate an understanding of the principles and features of thevarious embodiments of the invention, various illustrative embodimentsare explained below. Although exemplary embodiments of the invention areexplained in detail as being systems and methods for aligning a cutterhead on a pelletizer, it is to be understood that other embodiments arecontemplated, such as embodiments employing other types of machineryrequiring alignment. Accordingly, it is not intended that the inventionis limited in its scope to the details of construction and arrangementof components set forth in the following description or examples. Theinvention is capable of other embodiments and of being practiced orcarried out in various ways. Also, in describing the exemplaryembodiments, specific terminology will be resorted to for the sake ofclarity.

It must also be noted that, as used in the specification and theappended claims, the singular forms “a,” “an” and “the” include pluralreferences unless the context clearly dictates otherwise. For example,reference to a component is intended also to include composition of aplurality of components. References to a composition containing “a”constituent is intended to include other constituents in addition to theone named.

Also, in describing the exemplary embodiments, terminology will beresorted to for the sake of clarity. It is intended that each termcontemplates its broadest meaning as understood by those skilled in theart and includes all technical equivalents which operate in a similarmanner to accomplish a similar purpose.

Ranges may be expressed herein as from “about” or “approximately” or“substantially” one particular value and/or to “about” or“approximately” or “substantially” another particular value. When such arange is expressed, other exemplary embodiments include from the oneparticular value and/or to the other particular value.

By “comprising” or “containing” or “including” is meant that at leastthe named compound, element, particle, or method step is present in thecomposition or article or method, but does not exclude the presence ofother compounds, materials, particles, method steps, even if the othersuch compounds, material, particles, method steps have the same functionas what is named.

It is also to be understood that the mention of one or more method stepsdoes not preclude the presence of additional method steps or interveningmethod steps between those steps expressly identified. Similarly, it isalso to be understood that the mention of one or more components in acomposition does not preclude the presence of additional components thanthose expressly identified.

The materials described as making up the various elements of theinvention are intended to be illustrative and not restrictive. Manysuitable materials that would perform the same or a similar function asthe materials described herein are intended to be embraced within thescope of the invention. Such other materials not described herein caninclude, but are not limited to, for example, materials that aredeveloped after the time of the development of the invention.

To facilitate an understanding of the principles and features of thisdisclosure, various illustrative embodiments are explained below. Inparticular, various embodiments of this disclosure are described as aself-aligning cutter hub. Some embodiments of the invention, however,may be applicable to other contexts, and embodiments employing theseembodiments are contemplated. For example and not limitation, someembodiments of the invention may be applicable to various types ofmachinery needing alignment, such as other types of cutting machinerywhere a cutter head is disposed proximate a die face. Accordingly, whereterms such as “pelletizer” or “pellet” or related terms or componentsare used throughout this disclosure, it will be understood that otherdevices, entities, objects, components, or activities can take the placeof these in various embodiments of the invention.

The materials described hereinafter as making up the various elements ofthe present invention are intended to be illustrative and notrestrictive. Many suitable materials that would perform the same or asimilar function as the materials described herein are intended to beembraced within the scope of the invention. Such other materials notdescribed herein can include, but are not limited to, materials that aredeveloped after the time of the development of the invention, forexample. Any dimensions listed in the various drawings are forillustrative purposes only and are not intended to be limiting. Otherdimensions and proportions are contemplated and intended to be includedwithin the scope of the invention.

As discussed above, a problem with conventional alignment methods isthat they are generally either heavy and/or expensive or are notsufficiently accurate. To address the shortcomings of conventionalsystems and methods, therefore, embodiments of the present invention canprovide a robust and accurate means of aligning the cutting head withthe face of the die. As described below, the system can use a number ofspherical or elliptical surfaces to provide a self-aligning cuttinghead. In this manner, the cutting head can be automatically aligned withthe die face upon reassembly of the machine (e.g., after service orrepair).

As shown in FIGS. 1 a-2 b, embodiments of the present invention cancomprise a driveshaft adapter 100 and a cutter adapter 200. In someembodiments, the driveshaft adapter 100 can comprise a concave sphericalsurface 105. The driveshaft adapter 100 can also comprise a plurality ofmounting bolt holes 110 and a first plurality of alignment pin holes115. In some embodiments, the alignment pin holes 115 can compriseelliptical or hemispherical mating surfaces 115 a, which will bediscussed more fully below. The driveshaft adapter 100 can also comprisea mounting hole 120 for mounting the driveshaft adapter 100 on adriveshaft, and/or connecting the driveshaft adapter 100 to a plugadapter 400, as described below. In some embodiments, the mounting hole120 can be threaded.

In some embodiments, the cutter adapter 200 can comprise a complementaryconvex spherical surface 205 that can mate with the concave surface 105on the driveshaft adapter 100. Of course, this geometry is somewhatarbitrary and the convex/concave surfaces could, for example, bereversed. In some embodiments, the cutter adapter 200 can also comprisea second plurality of alignment holes 210 with hemispherical orelliptical mating surfaces 210 a.

In some embodiments, the cutter adapter 200 can also comprise anexternal threaded surface 215 to enable a blade hub or cutter head orother components to be mounted thereon. In other embodiments, the cutteradapter 200 can comprise a bolting flange or other means for attachment.In some embodiments, the cutter adapter 200 can also comprise a mountinghole 220 with a hemispherical or elliptical mating surface 220 a.

As shown in FIGS. 3 a and 3 b, the system can also comprise a pluralityof alignment pins 300. In some embodiments, the alignment pins 300 cancomprise a rounded or elliptical head 305, a threaded portion 310 and ashoulder 315. As shown in FIG. 1 a, the alignment pins 300 can bedisposed in the alignment pin holes 115 disposed in the shaft adapter100 and the alignment holes 210 in the cutter adapter 200. In someembodiments, the rounded surface 305 of the alignment pins 300 can beadapted to fit the mating surfaces 115 a, 210 a of the alignment holes115, 210.

In some embodiments, the alignment pins 300 can further comprise threads310 and can be threaded into the alignment pin holes 115. In otherembodiments, the alignment pins 300 can be, for example and notlimitation, press-fit, welded, cast, or affixed with adhesive to theshaft adapter 100 and/or the cutter adapter 200. In still otherembodiments, the shaft adapter 100 (or cutter adapter 200) and thealignment pins 300 can be cast or forged from a single piece of metal toform a shaft adapter 100 with integral, or unitary, alignment pins 300(e.g., the shaft adapter 100 and pins 300 can be integrally manufacturedas a single piece of cast or forged metal).

In some embodiments, the alignment pins 300 can comprise, for example,tool steel, stainless steel, a heat treated stainless steel, or acombination thereof. In other embodiments, the alignment pins 300 cancomprise, for example, ceramic, plastic, titanium, or carbide materials.Of course, the alignment pins 300 can comprise other suitable materialsand are not intended to be limited to the aforementioned materials.

In some embodiments, the rounded head 305 of the alignment pins 300 canserve to transmit torque between the shaft adapter 100 and the cutteradapter 200. In this manner the head 305 and or shoulder 315 of the pins300 can be surface treated to improve lubricity and/or wear resistance.In some embodiments, the surface treatment can comprise a surfacehardness treatment including, for example and not limitation, polishing,electro-less plating, electroplating, plasma coating, composite diamondcoating, PVD coatings, hard anodizing, or combinations thereof. In otherembodiments, the surface treatment can include surface lubricitytreatments including, but not limited to, polishing, PTFE coating,graphite, molybdenum disulfide, hexagonal boron nitride, tungstendisulfide, or combinations thereof.

As shown in FIGS. 4 a-4 c, the cutter adapter 200 can be affixed to thedriveshaft adapter 100 using a plug adapter 400. The plug adapter 400can comprise a spherical or elliptical mating surface 405 configured tomate with the mating surface 220 a of the cutter adapter 200. The plugadapter 400 can also extend through the mounting hole 220 of the cutteradapter 200 to interface with the driveshaft adapter, as describedbelow.

In some embodiments, as shown in FIGS. 4 a-4 c, the plug adapter 400 cancomprise threads 410 that mate with the driveshaft adapter 100 to couplethe plug adapter 400 and the driveshaft adapter 100. In someembodiments, as shown in FIG. 5 a, the plug adapter 400 can comprise abolt 550 for this purpose. The bolt 550 can comprise a Torx®, Allen, orother suitable head 555 to enable the bolt 550 to be installed andtightened in the driveshaft adapter 100. Of course, in some embodiments,the bolt 550 can also comprise a threaded portion 560 to mate with athreaded portion of the driveshaft adapter 100. In other embodiments,the bolt 555 can be press-fit, or otherwise retained, in the driveshaftadapter 100.

In some embodiments, the plug adapter 400 can also comprise an o-ringgroove 415 to receive an o-ring 565 (FIG. 5 a) to seal greases, oils,and other products in and contaminants out. In some embodiments, theplug adapter can further comprise a collar or spacer 420, sized andshaped to accurately interface with the mounting hole 220 of the cutteradapter 200.

As shown in FIG. 5 a, the assembled system 500 can comprise a cutterhead 505, the cutter adapter 200, and the shaft adapter 100. In someembodiments, therefore, the shaft adapter 100 can be bolted to adriveshaft, or other power source, using a plurality of fasteners 510.The fasteners 510 can be, for example, bolts, screws, rivets, or pins.In some embodiments, the fasteners 510 can be socket head cap screwscountersunk in the face of the shaft adapter 100.

The shaft adapter 100 can further comprise a plurality of alignment pins300. In some embodiments, the alignment pins 300 can comprise threads310 and can threadably engage the shaft adapter 100. In otherembodiments, the alignment pins 300 can be press-fit, welded, orotherwise affixed to the shaft adapter 100. In still other embodiments,the alignment pins 300 can be, for example, integrally cast or forgedwith the shaft adapter 100 (i.e., the alignment pins 300 and shaftadapter 100 can be integral). In some embodiments, the shaft adapter 100and cutter adapter 200 can also comprise an o-ring groove 515 and ano-ring 520. In some embodiments, the o-ring 520 can seal between theshaft adapter 100 and the cutter adapter 200 to prevent oil and greasefrom escaping from the system 500 and to prevent water and debris fromentering the system 500. The o-ring 520 can also provide someflexibility at the interface between the shaft adapter 100 and thecutter adapter 200 enabling the two to pivot slightly.

In some embodiments, the cutter adapter 200 can be affixed to the shaftadapter 100 using the fastener and a plug adapter 400. In someembodiments, an external surface of the cutter adapter 200 can comprisethreads 215. In this manner, a cutter head 505 can comprisecomplementary threads 505 a for threadable engagement with the cutteradapter 200. In other embodiments, the cutter head 505 can be bolted,press-fit, braised, welded, or otherwise affixed to the cutter adapter200. In still other embodiments, the cutter adapter 200 and cutter head505 can be, for example, cast or forged as a single component (i.e., thecutter adapter 200 and cutter head 505 can be a unitary piece).

In still other embodiments, as shown in FIG. 5 b, the cutter head 505can comprise a mounting flange 580 with mounting holes 585, and thecutter adapter 200 can comprise a plurality of matching mounting holes590. In this manner, the cutter head 505 can be mounted to the cutteradapter 200 using a fastener 595 such as, for example and notlimitation, bolts, rivets, or pins.

In some embodiments, the cutter head 505 can further compriseremovable/replaceable cutting blades 505 b. This can enable the blades505 b to be removed and replaced and/or sharpened as necessary. In someembodiments, the blades 505 b can be attached to the cutter head 505using one or more fasteners 505 c. In other embodiments, the blades 505b can be integral with, adhered to, pinned, wedged, or otherwise affixedto the cutter head 505.

The cutter adapter 200, cutter head 505, and shaft adaptor 100 can bemade of, for example and not limitation, tool steel, stainless steel,heat treated stainless steel, or combinations thereof. In otherexemplary embodiments, the cutter adapter 200, cutter head 505, andshaft adaptor 100 can be made of ceramic, plastic, titanium, or carbidematerials. Of course, the cutter adapter 200, cutter head 505, and shaftadaptor 100 can be made of other materials as well and are by no meanslimited to the aforementioned materials. In some embodiments, thespherical surfaces 105, 205, 305, and 405 can be surface treated toimprove lubricity and/or wear resistance such as polishing, electro-lessplating, electroplating, plasma coating, PTFE coating, composite diamondcoating, or PVD coatings.

In other embodiments, the aforementioned surface treatments can compriseone, two, and potentially multiple processes including, but not limitedto, cleaning, pickling, acid-wash, base-wash, nitriding, carbonitriding,electroplating, electro-less plating, flame spraying including highvelocity applications, thermal spraying, plasma spraying, sintering, dipcoating, powder coating, vacuum deposition, chemical vapor deposition,physical vapor deposition, sputtering techniques, spray coating, andreactive coatings utilizing thermal, radiational, and/or photoinitiationcure techniques, nitriding, carbonitriding, phosphating, and forming oneor more layers thereon. Materials applied utilizing these processes cancomprise metals, inorganic oxides, inorganic carbides, inorganicnitrides, inorganic carbonitrides, corrosion inhibitors, sacrificialelectrodes, and polymers including urethanes and fluorourethanes,polyolefins and substituted polyolefins, polyesters, polyamides,fluoropolymers, polycarbonatespolyacetals, polysulfides, polysulfones,polyamideimides, polyethers, polyetherketones, silicones, and the like.

FIG. 6 depicts the system 500 installed in a pelletizer 600. Thepelletizer 600 includes a flow of molten plastic 650, or other material,flowing through a die 620 and then extruded through a series ofextrusion holes 655 in a die face 625. As the material 650 is extruded,the cutter blades 505 b cut the ribbons of extruded plastic 650 off intouniform pellets. The pellets then enter a cooling water flow 660, wherethey solidify into substantially perfect pellets.

A driveshaft 615 and power source 610 can be attached to the shaftadapter 100 via a plurality of fasteners 510. Power can then betransmitted from the shaft adapter 100 to the cutter adapter 200 viaplurality of alignment pins 300 with rounded heads 305. In someembodiments, the cutter adapter 200 can transfer power to the cutterhead 505.

The hemispherical, spherical, or elliptical surfaces 105, 205, 305, and405 used to connect the components of the system 500 combine to providea system 500 that enables the cutter adapter 200 to pivot throughseveral degrees of motion to enable the cutter blades 505 b toautomatically be aligned with the die face 625. As mentioned above, thisself-aligning feature enables the cutter blades 505 b to operatesubstantially parallel to the die face 625, which reduces wear on theblades 505 b and the die face 625. This reduces maintenance and partscosts and also provides more consistent pellet geometry. Of course, thesystem could also be used on other machines in which alignment of thecutting blades and die face (or other cutting surface) is desirable.

FIG. 7 a depicts the system 500 in a parallel position. In other words,if the system 500 is assembled and there is no misalignment between thecutter head 505 and the die face 625, then no adjustment is necessary.As shown in FIG. 7 b, however, if the system 500 is assembled and aslight misalignment exists between the cutter head 505 and the die face625, the system 500 automatically tilts to realign the cutter head 505and the die face 625. As shown, the cutter head 505 can pivot on thecurved surfaces 105, 205, 305, and 405, while the o-ring 520 slightlycompresses on one side and slightly expands on the other. This enablesthe system 500 to pivot as necessary, while still being sealed.

In some embodiments, the system can pivot up to 5 degrees in eitherdirection. In other embodiments, the system can pivot up to 2 degrees ineither direction. In still other embodiments, the system can pivot up to1 degree in either direction. More or less travel can be provided fordifferent situations and represents a compromise between precision andflexibility.

While several possible embodiments are disclosed above, embodiments ofthe present invention are not so limited. For instance, while severalpossible configurations of materials for the cutter adapter 200, cutterhead 505, and shaft adaptor 100 have been disclosed, other suitablematerials and combinations of materials could be selected withoutdeparting from the spirit of embodiments of the invention. In addition,the location and configuration used for various features of embodimentsof the present invention can be varied according to a particularpelletizer (or other machine), factory, or application that requires aslight variation due to, for example, the materials being manufacturedand/or space or power constraints. Such changes are intended to beembraced within the scope of the invention.

The specific configurations, choice of materials, and the size and shapeof various elements can be varied according to particular designspecifications or constraints requiring a device, system, or methodconstructed according to the principles of the invention. Such changesare intended to be embraced within the scope of the invention. Thepresently disclosed embodiments, therefore, are considered in allrespects to be illustrative and not restrictive. The scope of theinvention is indicated by the appended claims, rather than the foregoingdescription, and all changes that come within the meaning and range ofequivalents thereof are intended to be embraced therein.

What is claimed is:
 1. A system comprising: a driveshaft adapter with afirst side and a second side and comprising: a first plurality ofalignment holes disposed on the first side; and a concave surfacedisposed on the first side; a cutter adapter with a first side and asecond side and comprising: a second plurality of alignment holesdisposed on the second side; and a convex surface disposed on the secondside; and a plurality of alignment pins each with a first end and asecond end, each of the first ends comprising a rounded surface sizedand shaped to be in slideable engagement with one or more of the firstand second plurality of alignment holes; wherein the cutter adapter canpivot on the convex surface, concave surface, and the rounded surfaceson the plurality of alignment pins to align the cutter adapter with adie face.
 2. The system of claim 1, further comprising: a concavesurface disposed on the first side of the cutter adapter; a plug adaptercomprising a convex surface sized and shaped to be in slideableengagement with the concave surface on the first side of the cutteradapter, the plug adapter further configured to be in engagement withthe driveshaft adapter.
 3. The system of claim 2, wherein one or more ofthe concave surface of the driveshaft adapter, the convex surface of thecutter adapter, the concave surface of the cutter adapter, and theconvex surface of the plug adapter are surface treated by one or more ofpolishing, electro-less plating, electroplating, plasma coating, PTFEcoating, composite diamond coating, or PVD coating.
 4. The system ofclaim 2, the plug adapter further comprising a first seal groovedisposed on the convex surface; and an adapter seal sealing the convexsurface of the plug adapter and the concave surface on the first side ofthe cutter adapter.
 5. The system of claim 4, wherein the adapter sealis an o-ring.
 6. The system of claim 1, the cutter adapter furthercomprising a first threaded surface disposed on an external, perimeterof the cutter adapter; and a toroidal cutter head comprising a pluralityof cutting blades disposed on an external, perimeter surface and asecond threaded surface disposed on an internal, perimeter surfacethreadably engageable with the first threaded surface disposed on theexternal, perimeter of the cutter adapter.
 7. The system of claim 6,wherein each of the plurality of cutting blades further comprise one ormore mounting fasteners detachably coupling the plurality of cuttingblades to the toroidal cutter head.
 8. The system of claim 1, furthercomprising: a first groove disposed on the first side of the driveshaftadapter; a second groove disposed on the second side of the cutteradapter; and a first seal for sealing the first surface of thedriveshaft adapter to the second surface of the cutter adapter.
 9. Thesystem of claim 1, wherein the second end of each of the plurality ofalignment pins comprises threads for threadable engagement with one ofthe driveshaft adapter and the cutter adapter.
 10. The system of claim1, further comprising a cutter head attached to the cutter adapter, andwherein a force applied to the cutter head causes the cutter adapter topivot.
 11. The system of claim 1, wherein the rounded surface on theplurality of alignment pins comprises one or more of a surface hardnesstreatment and a surface lubricity treatment.
 12. A system comprising: apower source; a driveshaft, with a first end and a second end, the firstend detachably coupled to the power source; a driveshaft adapter with afirst side and a second side, the first side detachably coupled to thesecond end of the driveshaft, the driveshaft adapter comprising: a firstplurality of alignment holes disposed on the second side; and a concavesurface disposed on the second side; a cutter adapter with a first sideand a second side and comprising: a second plurality of alignment holesdisposed on the first side; and a convex surface disposed on the firstside; and a plurality of alignment pins each with a first end and asecond end, each of the first ends comprising a rounded surface inslideable engagement with one or more of the first and second pluralityof alignment holes; wherein the cutter adapter pivots on the convexsurface, concave surface, and rounded surfaces on the plurality ofalignment pins.
 13. The system of claim 12, further comprising: a dieface comprising a plurality of extrusion holes; a cutter head attachedto the cutter adapter and comprising cutting blades; wherein the cutteradapter pivots to align the cutting blades with the die face in parallelarrangement.
 14. The system of claim 13, wherein the cutting bladescontact the die face and the resulting force causes the cutter adapterto pivot.
 15. The system of claim 12, the cutter adapter furthercomprising a first threaded surface disposed on an external, perimeterof the cutter adapter; and a toroidal cutter head comprising a pluralityof cutting blades disposed on an external, perimeter surface and asecond threaded surface disposed on an internal, perimeter surfacethreadably engageable with the first threaded surface disposed on theexternal, perimeter of the cutter adapter; wherein the cutter adapterpivots to align the plurality of cutting blades with the die face inparallel arrangement.
 16. The system of claim 12, wherein the driveshaftadapter and the plurality of alignment pins are integrally manufactured.17. The system of claim 12, wherein the rounded surface on the pluralityof alignment pins comprises a surface hardness treatment.
 18. The systemof claim 12, wherein the rounded surface on the plurality of alignmentpins comprises a surface lubricity treatment.
 19. The system of claim12, wherein one or more of the concave surface of the driveshaft adapterand the convex surface of the cutter adapter are surface treated by oneor more of polishing, electro-less plating, electroplating, plasmacoating, PTFE coating, composite diamond coating, or PVD coating.
 20. Asystem for aligning cutting blades with a die surface, the systemcomprising: a driveshaft adapter connected to a driveshaft and having aconcave surface disposed on a first side; a cutter adapter; a plugadapter with a convex surface disposed on a first side; a cutter headattached to the cutter adapter and comprising cutting blades; whereinthe cutter adapter pivots between the concave surface of the driveshaftadapter and the convex surface of the plug adapter in response to aforce applied to the cutting blades.
 21. The system of claim 20, whereinthe cutter adapter comprises a convex surface in slideable engagementwith the concave surface of the driveshaft adapter and a concave surfacein slideable engagement with the convex surface of the plug adapter. 22.The system of claim 20, further comprising a plurality of alignment pinsto transfer torque from the driveshaft adapter to the cutter adapter,wherein the alignment pins do not prevent the cutter adapter frompivoting.
 23. The system of claim 22, wherein the alignment pinscomprise a rounded surface with one or more of a surface hardnesstreatment and a surface lubricity treatment.
 24. The system of claim 20,wherein one or more of the concave surface of the driveshaft adapter andthe convex surface of the plug adapter are surface treated by one ormore of polishing, electro-less plating, electroplating, plasma coating,PTFE coating, composite diamond coating, or PVD coating.